Cars often have a wireless access control with an electronic key and an electronic lock. These keys, comprise a transponder for exchanging data with a control unit of the car via radio frequency (RF) signals to verify that the key ‘matches’ the car. If the key matches, the doors are unlocked or locked and/or the engine is started upon demand. Early systems unlocked or locked all doors when a user pushed an unlock button or a lock button, respectively of the key. Thus the function of locking/unlocking of the door was associated to the respective button. Currently, there are systems available that measure the distance of the key to doors and open only the door being next to the key.
As suggested e.g. in WO 2014/053411 the key may as well be used to remote control additional functions of the car, e.g. opening or closing of a window or a trunk lid, switching parking lights on or off, opening a garage door and the like. These additional functions are associated to a particular movement of the key in space which is detected by acceleration sensors. These movements replace actuating a corresponding push-button being associated with the corresponding function. In addition, the position of the key is determined and used to determine which door or window is next to the key, to activate that particular window or door lock if a corresponding command is detected.